Musgrave's Spacewalk Scenerio

Now that Story Musgrave's "spacewalk inspection" theory was given time on
the ABC Special about Columbia, it seems according to him that it was quite
possible for an astronaut to actually inspect the leading edges and even the
underside of the Shuttle while in orbit. I just don't understand how an
astronaut without a maneuvering backpack could get under the Shuttle.
There's no handholds and I imagine that's the most obvious handicap to such
an EVA. Is he being a bit too flippant about such a scenario or was it
actually possible?

T.B.

On Tue, 08 Jul 2003 06:21:06 GMT, "TB" wrote:

Now that Story Musgrave's "spacewalk inspection" theory was given time on
the ABC Special about Columbia, it seems according to him that it was quite
possible for an astronaut to actually inspect the leading edges and even the
underside of the Shuttle while in orbit. I just don't understand how an
astronaut without a maneuvering backpack could get under the Shuttle.
There's no handholds and I imagine that's the most obvious handicap to such
an EVA. Is he being a bit too flippant about such a scenario or was it
actually possible?

He was talking about an EVA to inspect the leading edge, but of course nobody
knew at the time that's where the problem was, everyone thought it was
underneath, perhaps near the landing gear doors.

But to my knowledge, no, without a SAFER unit or the EVA crewmember going
tetherless, there's no way to get underneath the orbiter except near the ET
doors in back, and even that's a risky kludge.

Story has mocked up and detailed a scenario he feels (and he should know)
where one astronauts uses the body of another astronaut as a handhold to
crawl over the edge and view the leading edge and some of the underbelly.
You have to remember however that most everyone at NASA felt the foam hit
far under the wing, near the land gear doors and even Story has yet to
explain how he could as he said "place human eyes 4 inches from the problem"
if the damage had been to the door area. Now the truth is if they had sent
the astronauts to go at least look "over" the edge they would have been
stunned to see the problem was with the edge and not the underbelly and
Story's method would have gotten them a close and personal look at
devesating damage.

"TB" wrote in message
. ..
Now that Story Musgrave's "spacewalk inspection" theory was given time on
the ABC Special about Columbia, it seems according to him that it was
quite
possible for an astronaut to actually inspect the leading edges and even
the
underside of the Shuttle while in orbit. I just don't understand how an
astronaut without a maneuvering backpack could get under the Shuttle.
There's no handholds and I imagine that's the most obvious handicap to
such
an EVA. Is he being a bit too flippant about such a scenario or was it
actually possible?

T.B.

"TB" wrote in
:

Now that Story Musgrave's "spacewalk inspection" theory was given time
on the ABC Special about Columbia, it seems according to him that it
was quite possible for an astronaut to actually inspect the leading
edges and even the underside of the Shuttle while in orbit. I just
don't understand how an astronaut without a maneuvering backpack could
get under the Shuttle. There's no handholds and I imagine that's the
most obvious handicap to such an EVA. Is he being a bit too flippant
about such a scenario or was it actually possible?

He's taking advantage of hindsight. The damage is now known to have been on
the leading edge; during the flight, it was thought to have been farther on
the underside, near the landing gear doors.

Musgrave's procedure would have been for one EVA astronaut to tether
himself to a latch on the payload bay door (hey, maybe even the very latch
that Tom Wheeler claims is the "hole"...), put his feet on the door and
stand upside down, then a second EVA crewmember would tether himself to the
first and stand on his shoulders. That gets the second crewmember's
eyeballs to the leading edge, but not nearly far enough to see the landing
gear doors.


--
JRF

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I thought Story M. was getting a bit riled up and perhaps started to
exaggerate for emphasis. Originally, the idea that the astronauts
would do a spacewalk all the way underneath the shuttle and wander all
over looking at tiles was deemed too difficult without handholds.
Without handholds they would be flapping about aimlessly and end up
kicking/standing on the fragile tiles. I believe Story was talking
about a spacewalk to look at the RCC panels on the edge - for this he
is thinking they could have been tethered to the cargo bay door area
and then peer over the edge. They would remain on top of the orbiter
and just look over the edge. This would be more feasible but no one
seemed to think at NASA that the foam hit the leading edge so they
wouldn't have been interested in looking there anyway. Also, everyone
seemed to believe the RCC panels were nearly indestructible.

"TB" wrote in message . ..
There's no handholds and I imagine that's the most obvious handicap to such
an EVA. Is he being a bit too flippant about such a scenario or was it
actually possible?

It's not just Musgrave. At the CAIB's request, NASA officially looked at
contingency repairs and found a repair EVA (not just inspection) theoretically
possible. See below.

I agree the hindsight of knowing the damage site makes it easier. I'm sure
NASA would have tried this had the TPS damage assessment been
more serious looking or the ascent photography better.

An inspection/ repair EVA is definitely a highly improvised risk. But every
flight is already prepared to go underneath the aft vehicle to fix a stuck
ET umbilical door. Risky as that is, at least they have a procedure for it,
so it's not like there's been no planning for EVAs beyond the payload bay.
----------------

http://cbsnews.cbs.com/network/news/space/current.html

"They inventoried everything that was on board the Columbia," Gehman said.
"There are two EVA suits. They devised a successful way to get out to the area of
the damage without further damage to the TPS (thermal protection system). They
devised a way that they thought they could work out there and they ... came up with
a patch that they would jam stuff in the hole."

-- Joe D.

"Joe D." wrote in
:

http://cbsnews.cbs.com/network/news/space/current.html

"They inventoried everything that was on board the Columbia," Gehman
said. "There are two EVA suits. They devised a successful way to get
out to the area of the damage without further damage to the TPS
(thermal protection system).

Unfortunately, that's not what the NASA presentation to the CAIB said. It
specifically stated that the repair EVA carried high risk of further
vehicle damage. (I will be charitable and assume Mr. Gehman simply confused
the repair EVA with the lower-risk inspection EVA).
--
JRF

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check "Organization" (I am not assimilated) and
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I understand that using a device like a pair of sticky-pad gloves to allow
an EVA person to kind of crawl to any part of the vehicle is out of the
question, but I'm wondering why. Do adhesives work in space?
Or another though along same lines: obviously handrails cannot be provided
just anywhere they might need them, but perhaps a set of spot electro-magnets
can be planted just under the tile surface of the orbiter that can be
activated on demand and used with magnetic gloves or a removable magnetic
handrail.

Jorge R. Frank wrote:
"TB" wrote in
:

Now that Story Musgrave's "spacewalk inspection" theory was given time
on the ABC Special about Columbia, it seems according to him that it
was quite possible for an astronaut to actually inspect the leading
edges and even the underside of the Shuttle while in orbit. I just
don't understand how an astronaut without a maneuvering backpack could
get under the Shuttle. There's no handholds and I imagine that's the
most obvious handicap to such an EVA. Is he being a bit too flippant
about such a scenario or was it actually possible?

He's taking advantage of hindsight. The damage is now known to have been on
the leading edge; during the flight, it was thought to have been farther on
the underside, near the landing gear doors.

Musgrave's procedure would have been for one EVA astronaut to tether
himself to a latch on the payload bay door (hey, maybe even the very latch
that Tom Wheeler claims is the "hole"...), put his feet on the door and
stand upside down, then a second EVA crewmember would tether himself to the
first and stand on his shoulders. That gets the second crewmember's
eyeballs to the leading edge, but not nearly far enough to see the landing
gear doors.

Andrey Serbinenko wrote in
:

I understand that using a device like a pair of sticky-pad gloves to
allow an EVA person to kind of crawl to any part of the vehicle is out
of the question, but I'm wondering why. Do adhesives work in space?

They work. It's important to keep context he for a hypothetical post-
return-to-flight repair EVA, some form of worksite stabilization is
required, and adhesive pads are one concept being considered. You don't
want adhesive gloves, though - there are some times you need the gloves
*not* to stick to something. But for a hypothetical STS-107 "what-if"
scenario, such materials were not available to the crew.

Or another though along same lines: obviously handrails cannot be
provided just anywhere they might need them, but perhaps a set of spot
electro-magnets can be planted just under the tile surface of the
orbiter that can be activated on demand and used with magnetic gloves
or a removable magnetic handrail.

Most of the areas where you'd need the electromagnets are not accessible
from the inside during flight, so you'd need to put them in place before
launch, and you'd need at *lot* of them. And they'd have to be very strong
electromagnets to work through the thickness of the tile. So the weight
penalty would be extremely high. Not a practical idea. You're better off
using a boom or truss to anchor the EVA crewmember to the RMS, and use
adhesive pads to control boom flex.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

"Andrey Serbinenko" wrote in message ...
I understand that using a device like a pair of sticky-pad gloves to allow
an EVA person to kind of crawl to any part of the vehicle is out of the
question, but I'm wondering why. Do adhesives work in space?

The original Martin Marietta repair kit (never fully developed) included a
work platform an MMU-equipped astronaut would maneuver into position. Then
adhesive pads would hold it in place on the orbiter belly. The pad
adhesion could be controlled via electric currents. See sidebar
in this Orlando Sentinel article:

http://tinyurl.com/75q9

Except for one Hubble servicing mission, all future shuttle flights
will go to ISS, so it's possible an elaborate self-contained repair
capability might not be needed. However even ISS-bound flights
can fail to reach ISS due to booster underperformance, etc, or the
docking machinery could fail. So they probably need at least some
minimal self-contained inspection/repair capability.

-- Joe D.